This invention relates to the preparation of allyl chloride. In one aspect, the invention relates to upgrading by-products formed during the allyl chloride preparation to increase the yield of allyl chloride.
Allyl chloride is used commercially as the starting material in the manufacture of epichlorohydrin and glycerine. The principle commercial method for manufacturing allyl chloride is the thermal chlorination of propylene. During this process, propylene and chlorine are mixed at an elevated temperature rapidly enough to obtain reasonable yields of allyl chloride. However, this process forms by-products such as 1,2-dichloropropane, 1,3-dichloropropene, and other mono-, di-, and tri-chlorinated C.sub.3 's. These by-products are used as the feed to preparation of more highly chlorinated hydrocarbons or are burned with heat and the chlorine values recovered as HCl. It would be desirable if these by-products could be converted to allyl chloride to obtain better yields of the desired product.
It is therefore an object of the present invention to provide an improved process for production of allyl chloride. It is a further object of the invention to upgrade by-products of an allyl chloride manufacturing process to useful products.